Internal-combustion engine



May 12, 1925.

G. MELLEN INTERL lCOMBU'STION ENGINE Filed sept. 11, 1915 @meh/hozPatented May 12, 1925.

PATENT OFFICE.

GRENVILLEHLLEN, CBANFOBD, NEW JERSEY.' i

rN'rEnNnrcoMnUsiTIoN ENGINE.

To all 'whom it may concern Be it known that I, GRmIVILLE MELLEN, acitizen of the United States, residin at Cranford, in the county ofUnion4 and tate of New Jersey, have invented certain new and usefulImprovements in Internal-Combustion Engines,-of which the following is aspecification.

'My invention relates to means for maintaining the power of aeroplaneengines at varying altitudes, and has forits ypurpose to provide suchengines with means for compensating for diminution of `power as theaeroplane rises into regions of lower barometrl'c pressure.

At higher altitudes the barometric pres-` sure is less, and there is asmaller quantity of air, i. e. a less amount-of oxygen, in a givenvolume, so that the power of the explosion is less than at sea-level,since there is not the same quantity of oxygen in the combustion chamberas at sea-level, and the density of the lexplosion gases is less.

My invention therefore comprises means for automatically supplyingto thecombustion chamber in augmentation of the normal charge, an additionalcharge of oxygen, preferably as compressed air, to produce a powerfulexplosivemixture; or for automatically increasing the supply to the cyl`inder of additional excess air and gasoline vapor; or for automaticallyincreasing the l supply to thewcylinder of explosive mixture.

My invention further' includes the feature of supplying to the cylinderof the engine gas of such density` as to insure the presence t in thecylinder chamber of gas in `suilicient mass to insure an effectiveexplosion stroke.

-I prefer toA use, in the practicalembodimenty of thisl invention, anengine of the four-stroke cycle type having multiple pairs Mof enginesvwith the pistons of each pair connected to the same crank, and arrangedin such4 manner that the compression of the su rcharge of air orexplosive mixture is eted by each pair of pistons in the same crankcase. vSuch an engine is disclosedin detail .in my application Ser. No.214,562, Vfiled January 30,1918.

In the present application I have illus trated diagrammatically such anengine, to-4 gether with the automatic barometrically operated device bywhich the additionall gaseous mixture or air, the supercharge iscontrolled.

Application led September 11, 1918. Serial No. 258,629.

Figure 1 is a diagram of the system, the engine being shown in section.y

Fig. 2 is an elevation of the engine with .a portion of the crank casingbroken away.

Fig. 3 is a detail of the rotatable sleeve valve and connecting ports.

Referring to vthe drawings, A is one of the enginelcylindes, havinginlet vvalve 1 and exhaust valve 2 at its upper portion, and portopenings 3, located just above the top of the piston 4 when at itslowermost position. The cylinder has an'exten'sion or skirt having twosets of port openings 5,l 6, the upper ports 5 opening into an annularchamberin thecasing, connecting with the port openingsv 3 in thecylinder, and the n lower portj openings 6 arranged to communiing gas isadmitted. The sleeve valve 9 1s constantly rotated by means of a gear 10at its top meshing with a pinion on the cam shaft 11, from which theinlet and 'exhaust valves are operated in the usual manner, this camshaft 11 being driven at the usual 1-2 ratio,.from the crank shaft 1,2by a' chain, as shown inv dotted lines, this chain" also driving theshaft of the magneto 13. The chambers or manifolds 7 and 8 are connectedat their inner ends to the ported upper portion of the crank-case, andare .provlded with valves 14, 15 for controlling the quantity ofexplosive mixture or air admitted to the crank case. A carburetor 16 isconnected to a manifold, from which supply pipes 18 lead to the inletvalves of each cylinder; and a-second carburetor 17 is 4connected to themanifold 8 to supply fuel to the crank-case chamber. The crank shaft isprovided with filling disks -40, arranged tol diminish the free space inthe crank cases as much as possible. The open ends of each pair ofcylinders are connected to the same crank case, so. that the volume ofexplosive mixture or air sucked in by the two pstonslon their upwardstrke is subsequently compressed upon their downward stroke into therela-A lating flow than if the supercharge were drawn from a crank caseconnected to a single cylinder.

The barometric control device may consist of an air-tight chamber 100havin a corrugated wall, one end of the cham' r being fixed and theother connected to a lever 101, whose outer end engages a lug orprojection 102 on a slidingv rod 103, to y which lug is -pivoted a link105 secured to the operating arm of a butterfly valve 15 in the inletpipe of the gas manifold 7 through whichair is supplied to thecrankcase. .In order to permit of independent control by the operator alever 108, also engaging the lug 102, may be connected by link 109 topedal-lever 110. Either automatic or manual vl.control is thuspermitted.

As shown the crank case is provided with duplicated means for admittinga charge thereto, one Vof such admission means being provided with 'acarburetor. Either air or vexplosive mixture may thus be introduced intothe crank case. As illustrated, the barometric device 100 controls thesettings of both valves 14 and 15, since the valves are connected by alink 106, but it is obvious that the barometric device may be arrangedto operate but onejvalve or it may control both valves but throughindependent connections.

`In operation of my invention, the car-` buretor 16 and its air supplyare carefully adjusted to provide for the adequate engine power atsea-level or any desired altitude representing standard atmosphericlconditions, the crank-case gas admission valve be- Ving setto admit onlysuch amount of air that at sea level, there will b e little if anycompression in the lcrank case. It will be evident that as the aeroplanerises this carburetor adjustment will provide a mixture which will betoo rich at the higher levels wherethere is less air and hence lessoxygen. The automatic pressure device will, however, by admittingadditional air and fuel Lto the crank case, supply an additional anddenser mixture, and where air or lean mixture is used the additional oxyen for more nearly complete combustion o the fuel or fuel-va or 1sprovided.

Furt er, it. has 'been demonstrated in ulated mixture of vaporized fueland air engine can made to develop'r from 30% to 40% additlonal power,for the reasons describedv in a recent application led by me onSeptember 11, 1918,/Ser. No. 253,630 reto mechanism" for obtainingsupercharge. k Myinvention therefore also comprises the feature ofautomatically or manually putractice that bysupplying, as from a car-Vuretor to thecrank case, a properly regting into operation the fuelmixture supercharge mechanism.

While it has heretofore been suggested'to use crank-case compression ofa fuel-gas mixture, the compressed mixture has been introduced into thecylinders not only at the end of the suction or admission stroke, butalso at the end of the explosion stroke to assist in scavenging. I havefound that the use of the compressed gas for scavenging is not onlyunnecessary, but is detrimental in that it lessens the gas pressure inthe crankcase and therefore does not afford the desirably highcompression to force the supercharge rapidly from the crank case duringthe necessarily short time that the lower or supercharge admission portsare open.

The cycle of operation of this engine is as follows z-Designating onecylinder by A and the other by B, and keeping in mind that both areconnected to one crank, and to a, common crank case, when as explosionor power stroke occurs in A, both pistons move inward toward the crankcase, the valves in A all being closed, while in B, the normal inletvalve 1 is open and the exhaust valve 2 closed and the normal charge ofexplosive gal is sucked into cylinder chamber B. en the pistons arrivenear the end of their inward stroke, the sleeve valve admits compressedgas (explosive mixture or-air or both) from the crank case, through port5 into annular chamber 20 and port 3 into cylinder B; but no connectionis made between the crank case and cylindery A. Duri g this same inwardstroke, the admission ports, 6, into the crank case have been keptclosed, sothat the gas in the crank case has been compressed.

On the succeeding outward stroke the explosion gases in A are exhaustedthrough its now opened exhaust valve 2, and the entire charge (normaland pressure superchar' e) in B is compressed. Also at the beginnlng ofthis outward stroke, the admission" ports 6 into the crank case havebeen opened, so that aquantity of air or explosive mixture equal involume to that of ytwo piston displacements less the residual amountwhich has remained undelivered on thev previous .supercharge deliveryhas been sucked into the crank case.

0n the next inward stroke, which is caused by the explosion of thecompressed charge in B, there are admitted into A, a normal chargethrough its normal inlet valve and a supercharge from the crank case,thecharge in the crank, case being compressed during the stroke.l On thefourth or outward stroke ofthe cycle, the explosion gases are driven outof B, `without any communication having been established between it andthe crank case, the charge in A is compressed, and afresh charge issucked mto the crank case. Y

l free space within the crank case proper is reduced to a minimum, andthe charge is compressed therein to obtain a maximum compressionpressure in this crank case cavity. Preferably also sleeve valves arevused, as they permit the use of relatively large port openings and avoidexhaust gas pockets, which are features of particular iinportance shownin my other applications above referred to,'in that the time duringwhich these ports are open, isvcomparatively short. Such valves canmoreover be made to effectively close the ports so that there is no lossofcompression, and.by proper location can readily be given the propertiming to enable the supercharge inlet, the normal inlet and exhaustports to open and close in such relation as to give the best results.

My invention thus provides means for maintaining the power of anaeroplane engine at varying altitudes, since by means of the compressionof the double cylinder volume of the charge into the restricted freespace in the 'crank case, there is provided a considerable volume of thecharge under superatmospheric'pressure suiiicient to cause a vigorousand rapid How of the compressed supercharge into the lower end of thecylinder, thus insuring that the cylinder space is not only, completelylled with a charge, but with a charge under superatmospheric pressure tothus compensate for the. lesser density of the normal charge.

I claim: f

1. The method of maintaining the power of internal combustion enginesunder varying atmospheric pressure which consists in supplying to theengine a normal charge appropriate for standard atmospheric pres# sureconditions and separately supplying in addition to the said normalworking charge a supercharge under pressure, the quantity of suchsupercharge being automatically varied to correspond with the variationsin atmospheric pressure. Y

2. An internal combustion engine having means for admitting to thecylinder, at the end of the fuel suction stroke, in addition to thenormal working charge of explosive mixture, av supercharge, means forcompressing the supercharge, and, barometrically actuated means forregulatlng the quantity of such supercharge in accordance withvariations in atmospheric pressure.

3. An internalcombustion engine having means for admitting to thecylinder a normal working vcharge of explosive mixture appropriate forstandard atmospheric pressure conditions and means for separatelysupplying in addition to the normal working charge a supercharge ofexplosive mixture, means for compressing the supercharge andbarometrically actuated means for regulating the quantity of suchsupercharge 1n accordance with variations in atmospheric pressure.

4. An internal combustion engine having means for admitting, in additionto and separately from the normal working charge of explosive mixture, asupercharge of air including means for compressing the air andbarometric-ally actuated means for regulating the quantity of such airin accordance with variations in atmospheric pressure.

5. An internal combustion engine having means for admitting, in additionto and separately from thenormal working charge of explosive mixture, asupercharge of air and a supercharge of air and fuel including means forcompressing the said supercharges, and barometrically actuated means forregulating the quantity of the supercharges in accordance withvariations of pressure.

6. An internal combustion engine having means for admitting, in additionto and separately from the normal working charge of explosive mixture, asupercharge, barometrically actuated means for regulating the quantityof the supercharge, and means for independently regulating the quantityof the supercharge,

7 An internal combustion engine of the ll-stroke cycle cranlecasecompression type having two cylinders whose pistons are connected to thesame crank, means for admitting a compressed charge from the crank casealternately into each cylinder near the end of its normal fuel-chargesuction stroke, means for excluding said compressed charge from thecylinder during the remainder of the cycle, and barometrically actuatedmeans for automatically varying the quantity of the compressed chargeadmitted into the cylinders, in accordance with variations inatmospheric pressure.

In testimony whereof, I aix my signature.

GRENVILLE MELLEN.

